Apparatus for heat-treating wire and the like



o. c. TRAUTMAN 2,556,349

June 12, 1951 APPARATUS FOR HEAT-TREATING WIRE AND THE LIKE Filed April 30, 1945 @"22" """1 066 000 000 ooi 'cf b Tflf/MMALY Acm470 INVENTOR OSCAR QTRAUTMAN JW/TCH D'V/CE iii ,4 BY 5 y \S ATTORNEYS Patented June 12, 1951 APPARATUS FOR HEAT-TREATING WIRE 7 AND THE LIKE Oscar C. Trautnian, Parma, Ohio Application April 30, 1945, Serial No. 591,159

5 Claims. 1

The present improvements, relating as indicated to the heat treatment of wire and the like, have more particular regard to the construction and mode of operation of a quenching bath through which heated strands of wire or other equivalent elongated products, such as strips, may be continuously passed for the purpose of cooling the same to a predetermined temperature. Such baths are widely used in metallurgical processes such as the heat treatment of carbon steel to secure definite desired physical conditions and. qualities and, as is well understood, it is usually important that the temperature to which the heated product is reduced should lie within a definite narrow range, so that such product, e. g. wire, may have uniform physical structure and qualities throughout its length.

One principal object of the invention is to provide a bath of the character in question, the temperature of which may be conveniently and automatically controlled irrespective of the fact that the heated material under treatment continuously delivers to the bath a substantial amount of heat. A further object is to provide a simple and compact form of apparatus for effecting such temperature control, particularly in the case of a bath which it is required should be maintained at a temperature suitable for an annealing or so-called patenting process, viz. in a range between 950 F. and 1100 F. v

v; While the present improvements are more especially adapted for use in a method of continuously heat treating wire and the like where the product is advanced longitudinally into and through a contact pot containing an electrically conducting liquid and quenching bath of molten metal in spaced relation thereto while a current of electricity is passed through the section of advancing material between the surfaces of the liquids in such baths such as will heat such material progressively to a desired maximum temperature as it enters such quenching bath, the present improved form of quenching bath may be equally advantageously used where the wire or like product is otherwise heated as by means of a furnace such as has long and familiarly been used for the purpose.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims, the annexed drawing and the following description setting forth in detail certain means and one mode of carrying out the invention, such disclosed means and mode illustrating, however, but one of various into and through a ways in which the principle of the invention may be used.

In said annexed drawing:

Fig. 1 is a broken longitudinal sectional view of a contact pot or bath through which the wire or like article that is to be annealed is preliminarily passed on its Way to the cooling or quenching bath;

Fig. 2 is similarly a broken longitudinal sectional view of the present improved quenching pot which will be located in spaced relation to the right of such contact pot and at a lower level;

Fig. 3 is a transverse sectional view of such quenching pot, the plane of the section being indicated by the line 33 Fig. 2; and

Fig. 4 is a schematic temperature control circuit for controlling the temperature of the quenching bath. 7

As indicated, the illustrated method of heating the wire W involves theuse of a contact pot I through which such wire, or preferably a plurality of wires will be passed on their way to the quenching pot 2. Said pots, and particularly the second thereof, will preferably be in the form 01 elongated shallow metal pans and they will be suitably supported in an insulating setting as shown. Each, moreover, will contain a metal such as lead which will assume a molten state at the temperature of operation involved. The

approximate level of such molten bath is indicated by dotted line 3 in Fig. 1 and by dotted line 4 in Fig. 2, and in order to maintain the wire as it traverses the respective pots below such level a guide or sinker 5 is provided in the contact pot and a similar guide-6 in the quench pot. These sinkers, as illustrated in Fig. 3, will preferably consist of transverse bars with a series of grooves '50:, in the one case and 6a in the other on the under side thereof corresponding in number with the wires which the apparatus is designed to handle.

Each wire as itleaves such contact pot I is guided over a sheave I into a downwardly inclining insulating tube 8, but out of contact therewith, and upon emerging from the lower end of such tube directly enters the bath of molten metal in the quench pot 2. By means of suitable leads (not shown) such contact and quench pots, and thus the molten baths respectively contained thereby, are connected in an electric circuit whereby a current of electricity such as will heat the advancing material progressively to a desired temperature as it enters such quenching bath is caused to pass through the portion of such material, e. g. wire W,which extends from the first bath to the second. The method of thus heating a continuously advancing wire or equivalent product which forms no part of the present invention is fully shown and described in U. S. Patent No. 2,300,329 to W. H. Wood et al., dated October 27, 1942, to which reference is made for a further understanding thereof.

Whether heated by electrical means as just set forth or by the. more familiar furnace, the wire at the point where it enters the second bath or quench pot will be brought to a relatively high temperature, e. g. in the neighborhood of 1500 F., and for the purpose of annealing or patenting the wire, such temperature requires to be reduced as previously stated to from 950 to 1100 F. Where, as contemplated, a plurality of wires is being simultaneously treated; in order to obtain uniform results it is important that the temperature throughout the quenching bath be maintained as uniform as possible both transversely as well as longitudinally. It is of course also necessary that the body of metal which constitutes the bath should be preliminarily raised to a temperature where it will be in molten state, otherwise the apparatus cannot function at all. Accordingly, inthe resent improved construction, interconnected heating and cooling means, the latter of special construction, are provided.

The heating means comprise a plurality of transversely extending immersion heaters 10 that are disposed in longitudinally spaced relation adjacent the bottom of the pan 2- which constitutes the quench pot, such heaters entering the latter through one of the side walls and being preferably of the electric resistance type whereby the amount of heat input can be closely regulated. Moreover, a sufficient number of such units will be employed so that the body of molten metal in the pan or pot may not only be quickly rendered molten, but brought approximately to the temperature at which the bath requires to be maintained for the treatment involved. However, since this temperature is substantially lower than that of the entering highly heated wires, the temperature of the bath would presently increase to a. point where no effective cooling action is obtained even though such heating units be entirely out out.

The cooling means provided to carry off the excess heat thus introduced into the bath by the entering highly h'eatedwires comprise in the first place a multiple series of passages l2 that extend longitudinally of the bottom wall or floor from a supply duct l3 adjacent the front endof said pot or pan, i. e. the end at which the wires W enter the bath, to a point a substantial distance from such end where such passages connect with a discharge duct 14. A similar multiple series of ducts l5 extend in the same manner along the respective side walls of the pot or pan from a common header l6 connected with a supply duct ll, these passages conveniently leading to the same discharge duct M as do the first-mentioned passages or they may be provided with a separate discharge if desired. Ducts l3 and H are connected with a common supply line [8- of air or other cooling fluid under pressure sufficient to cause the same to flow through the passages 12 and I5.

Extending along the respective sides of the pot or pan are ducts ZO-similarly connected with a common supply line 2| of air or equivalent cooling fluid and leading from said ducts is a series of transversely disposed cooling tubes 2 2 The latter, as best shown in Fig. '3, extend downwardly into the bath, thence transversely, and have upwardly directed discharge ends 23. Preferably, as shown in Fig. 2, these cooling pipes 22 will be arranged in groups of two or three, and such groups will be alternately connected with the duct 20 on the one side and the corresponding duct 20 on the other side of the pot or pan. It will be understood that the number of cooling pipes in such groups may be varied as well as the spacing thereof longitudinally of the pan, so as to provide a greater cooling effect at the front end of the latter where the wires W enter the bath. In any case, by having such cooling. pipes connected in the manner described, the cooling fluid will be caused to flow through successive pipes or groups thereof in opposite directions and thereby insure uniform cooling action throughout the transverse extent of the bath. Accordingly, the latter may be maintained at the same temperature for all of the entering wires W despite the lateral spacing thereof.

For the purpose of. controlling the several cooling means as well as the heating means thusprovided, a thermostat or for example a thermally actuated switch device 24 (see Fig. 4) will be provided responsive to the temperature at one or more. points in the bath. Such thermo-.. stat device 24 will be set so that upon initially heating the bath to bring. it to required molten state switch contacts in. said device will open whereby the heating units It) will be cut out, for example at a temperature of 1000 F. There-. upon the wires W brought to a temperature, for example of 1475. F., are caused to traverse the; bath and theefiect of the added heat thus supplied to the latter will immediately start to raise its temperature. As soon as such rise equals a predetermined number of degrees other switch contacts in the thermostat device will close and turn on the supply of cooling fluid to ducts 20 as by energizing the control means 25' in supplyline 2! and such fluid thus caused to flow trans! versely in opposite directions through alternate pipes 22 or groups of such pipes. If the. tem-. perature of the bath still continues to rise, still other switch contacts in the thermostat device 24 will close and turn on the supply of cooling fluid to ducts I3 and IT as by energizing thecontrolmeans 25 in supply line l8 whereby such fluid is caused to traverse the passages 12 and l-5 extending along the bottom and side walls of the pot or pan. Upon the temperature of the bath dropping below a prescribed maximum, for example 1010- F., the thermostat device 24 will operate to cut offthe supply of such cooling fluid to the last-mentionedducts, and if necessary the supply of such fluid to ducts 20.

In this manner the temperature of the bath may be controlled within very close limits while at the same time such temperature is maintained substantially uniform throughout the bath so that all of the wires passing through the same will be cooled down to the proper temperature for producing the desired annealing or patenting effect.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the means. and the steps. herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

I therefore particularly point, out and distinctly, claim as my invention:

1. Apparatus, for controlling the temperature of liquids, comprising a tank having passages in its bottom and side walls extending longitudinally from one end of said tank toward the other and leading from a divided duct at such one end, means for flowing a cooling medium through such divided duct into and longitudinally in one direction through such passages, heating means in said tank, tubes within said tank extending transversely thereacross in longitudinally spaced relation, means connected respectively to the opposite ends of successive tubes for flowing a cooling medium in opposite directions through successive tubes and thermostatic means affected by the temperature of the liquid to be controlled associated with said heating means and said cooling medium flowing means, said thermostatic means being arranged to turn ofi said heating means when the liquid in the tank attains a predetermined temperature and to turn on one of the cooling medium flowing means upon rise in temperature of the liquid above such predetermined temperature and to turn on both of the cooling medium flowing means upon still further rise in the temperature of the liquid in the tank.

2. Apparatus for controlling the temperature of liquids, comprising a tank having passages in its bottom and side walls extending longitudinally from one end of said tank toward the other and leading from a divided duct at such one end, means for flowing a cooling medium through such divided duct into and longitudinally in one direction through such passages, heating means in said tank, tubes within said tank extending transversely thereacross in longitudinally spaced relation, means connected respectively to the opposite ends of successive tubes for flowing a cooling medium in opposite directions through successive tubes and thermostatic means aifected by the temperature of the liquid to be controlled associated with said heating means and said cooling medium flowing means, said thermostatic means being arranged to turn off said heating means when the liquid in the tank attains a predetermined temperature and to turn on the cooling medium flowing means associated with said tubes upon rise in temperature of the liquid above such predetermined temperature and to turn on both of the cooling medium flowing means upon still further rise in the temperature of the liquid in the tank.

3. Apparatus for controlling the temperature of liquids, comprising a tank provided with coolant passages in its bottom and side walls extending from one end of said tank toward the other,

v a cooling medium supply duct connected to one end of such passages for flowing a cooling medium in one direction through such passages, heating means in the bottom of said tank above the aforesaid coolant passages, cooling tubes within said tank and above said heating means and extending transversely across said tank in longitudinally spaced relation, means for flowing cooling medium through said tubes, and control means responsive to the temperature of the liquid in the tank arranged to turn ofi said heating means when the liquid in the tank attains a predetermined temperature and to turn on one and finally both of said cooling medium supply means upon continued rise in temperature of the liquid above such predetermined temperature.

4. Apparatus for controlling the temperature of liquids, comprising a tank provided. with coolant passages in its bottom and side walls extending from one end of said tank toward the other, a cooling medium supply duct connected to one end of such passages for flowing a cooling medium in one direction through such passages, heating means in the bottom of said tank above the aforesaid coolant passages, cooling tubes Within said tank and above said heating means and extending transversely across said tank in longitudinally spaced relation, means for flowing cooling medium in opposite directions through successive tubes, and control means responsive to the temperature of the liquid in the tank arranged to turn off said heating means when the liquid in the tank attains a predetermined temperature and to turn on one and finally both of said cooling medium supply means upon continued rise in temperature of the liquid above such predetermined temperature.

5. Apparatus for controlling the temperature of liquids, comprising a tank provided with coolant passages in its bottom and side walls extending from one end of said tank toward the other, a cooling medium supply duct connected to one end of such passages for flowing a cooling medium in one direction through such passages, heating means in the bottom of said tank above the aforesaid coolant passages, cooling tubes within said tank and above said heating means and extending transversely across said tank in longitudinally spaced relation, means for flowing cooling medium in opposite directions through successive tubes, and control means responsive to the temperature of the liquid in the tank arranged to turn off said heating means when the liquid in the tank attains a predetermined temperature and to successively turn on the lastnamed cooling medium supply means and finally both of said cooling medium supply means upon continued rise in temperature of the liquid above such predetermined temperature.

OSCAR C. TRAUTMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 196,653 Gamgee Oct. 30, 1877 501,393 Wilisch July 11, 1893 1,091,120 Chase Mar. 24, 1914 1,412,152 Walpole Apr. 11, 1922 1,712,833 Mascuch May 14, 1929 1,808,152 Baily June 2, 1931 1,886,656 Droescher Nov. 8, 1932 1,971,314 Lauenstein Aug. 21, 1934 2,232,998 Cernohouz et a1. Feb. 25, 1941 2,315,230 Sticelber Mar. 30, 1943 2,320,531 Mojonnier June 1, 1943 2,322,777 Purnell June 29, 1943 2,324,517 King July 20, 1943 2,354,656 Annesley Aug. 1, 1944 2,356,068 Larsson Aug. 15, 1944 2,369,748 Nachtman Feb. 20, 1945 2,415,711 Sticelber Feb. 11, 1947 OTHER REFERENCES Metals Handbook, 1939 edition, page 325, American Society for Metals, Cleveland, Ohio. 

